Research On Protection And Mechanism Of Zhongfeng Xingnao Liquid Against Acute Cerebral Ischemia-reperfusion Injury In MCAO-R Model Rats

Objective: The purpose of this study was to confirm the prevention and treatment of acute cerebral ischemia-reperfusion injury by Zhongfeng Xingnao liquid(ZFXNL),and to screen the optimal therapeutic dose of ZFXNL;further explore the protection effort of ZFXNL against BBB during cerebral ischemia-reperfusion and related mechanisms.Provide theoretical basis for expanding the clinical use of ZFXNL.Method:114 male SD rats were divided into 6 groups according to the random number table method: sham control group,MCAO-R group,MCAO-R plus ZFXNL high-dose group(26.46g/Kg/d),MCAO-R plus ZFXNL medium-dose group(13.23/Kg/d),MCAO-R plus ZFXNL low-dose group(6.615/Kg/d),Edaravone group(4mg/Kg/d),of which 14 were in the sham control group and 20 in each other groups.Six days before the MCAO-R operation,the ZFXNL group was intragastric administration with ZFXNL once a day for 7 days,and the last administration was performed 2 hours before the MCAO-R operation.(1)The right middle cerebral artery occlusion operation was prepared by Zea-Longa’s method.The plug was pulled out after 1.5 hours of obstruction to form the right middle cerebral artery ischemia-reperfusion operation.The percentages of weight loss before MCAO-R operation and before execution in each group of rats.The Zea-longa test,Postural reflex test,Forelimb placing test,and Tail hang test were used to comprehensively evaluate the neural function of rats.(2)The brain was obtained by cardiac perfusion,and the brain tissue was stained by hematoxylin-eosin staining.Use graphic analysis software to calculate the proportion of infarct area and the percentage of cerebral hemisphere swelling in the infarction side.Observe the Ischemic penumbra area by optical microscope Pathological changes.(3)The permeability of the blood-brain barrier was evaluated by detecting the leakage of Evans Blue;the integrity of the structure of the BBB in the ischemic penumbra area was observed by transmission electron microscopy them the protective effect of ZFXNL on the BBB was evaluated.(4)In order to clarify the mechanism that ZFXNL protects BBB during brain I/R,use immunohistochemistry plus IOD test to detect the expression position and amount of tight junction proteins Claudin-5,Occludin and matrix metalloproteinases MMP-2,MMP-9 in ischemic penumbra area.Results: Compared with the MCAO group:(1)ZFXNL high and medium dose groups significantly improve the neurological function of MCAO-R rats,reduce the area of cerebral infarction,suppress the swelling of Cerebral infarct hemisphere,and improve the pathological changes of the ischemic penumbra area,which prove its prevention and treatment of CI-RI(P<0.05).(2)High and medium doses of ZFXNL significantly reduce the leakage of Evans Blue(P<0.05),protect the blood-brain barrier by maintain the integrity of TJ in the blood-brain barrier.(3)High and medium doses of ZFXNL significantly increase the expression of Claudin-5 and Occludin on vascular endothelial cells in the ischemic penumbra area(P<0.05);and inhibit the expression of MMP-2 and MMP-9 in neurons and glial cells(P<0.05).(4)ZFXNL high-dose group show serious diarrhea and obviously weight loss(P<0.05);ZFXNL’s high and medium dose apperance similar treatment effects with edaravone(P>0.05).Conclusions:(1)ZFXNL obviously prevent CI-RI,protect neurons in the ischemic penumbra area,improve neural function,reduce infarct area,and suppress the swelling of Cerebral infarct hemisphere.(2)ZFXNL obviously protecting the BBB in both structure and function by protect the integrity of the BBB structure and maintain the stability of the BBB function.(3)ZFXNL protects BBB by increasing the expression of Claudin-5,Occludin on vascular endothelial cells and inhibiting the expression of MMP-2,MMP-9 in neurons and glial cells.(4)The best therapeutic dose for ZFXNL to protect BBB and prevent CI-RI is the medium dose(13.23/Kg/d)...